Grate



Dec. 19, 1933. J. s THOMPSON GRATE Filed Aug. 19I 1930 za H /9 EMEAHE Patented Dec.` 19, 1933 UNITED STATES GaA'rE James sfrhomprsaln, "Newnoheue, N. Y., as-

, signor, by mesne assignments, to Waugh Equipment Company, New York, N. Y., a cor- 4poration of Maine g Application August 19, 1930. Serial No. 476,264

` Y 9 claims. (C1. 12s- 186) This invention relates to grate bars especially adapted for heavy duty purposes, as, for example, in locomotives, boiler furnaces, and the like. More particularly the invention is concerned with a grate bar which comprises a carrier and a plurality of fuel-supporting units removably mounted thereon.

In the co-pending application of Buckley, SerialV No. 338,352, filed February 8, 1929, now Patent No. 1,884,557, October 25, 1932, there is disclosed a grate bar of the general construction above described. As the Buckley bar hasbeen customarily made, the carrierv and units are made of cast iron and a `single grate bar has substantial weight. In addition, it sometimes occurs that during severe service, the units may crack across in the vicinity of their mid-points, the two parts of the unit fallingV clear of the carrier into the ash pan and leaving an opening in the grate. While this is not a frequent occurrence, it represents apotential disadvantage of the Buckley construction.

The present invention is accordingly directed to the provision of a grate bar of the Buckley type which is considerably lighter than a bar of similar size made of cast iron throughout and which includes units provided with reinforcing means which tend to prevent cracking and which operate, if fracture occurs, to prevent the unit from falling from the' carrier bar. This result is obtained by making the unitin part of cast metal and in part of sheet stock, the sheet portion of the unit being hollow Yso that a substantial lightening of the weight is obtained. y

For a better understanding of the invention,

' reference may be had to the accompanying drawing, in which Y Fig. 1 is a cross-sectional view of a grate bar constructed in accordance` with the invention showing one unit in side elevation;

Figs. 2 and 3 are sectional views on the lines 2--2 and 3-3 of Fig. 1;

Fig. 4 is a fragmentary side elevation of the grate bar; and

Fig. 5 is a plan view of the unit.

In the drawing, the grate bar is illustrated as including a carrier which comprises a web having an upstariding centering flange 11 lengthwise thereof and provided with a strengthening rib 12 projecting downwardly from its under surface. Also projecting downwardly from the web is a shaker arm 13 of usual construction. The web terminates in upstanding arms 14 provided with supporting means which may take the form of trunnions 15. Y Y

Mounted on the carrier is a plurality of fuelsupporting units each of which comprises a bottorn-'plate 16 which may be made of cast iron and a hollowv top or cap member 17 of sheet stock preferab'ly formed by stamping operations.

AThe cap member is formed on one or both faces with vertical lugs 18 defming between them air passages 19 for the upward ow of air from theashpan to the fuel bed and above each lug are fuel-supporting projections 20 which are preferably arranged in groups of four, two projections of each group lying above the lug and two lying above the main body of the cap member adjacent the lug. The projections are separated by intersecting air. channels 21 and 22, the latter 'communicating with the air passages 19 so that a wide distribution of air to the fuel supported on the unit is obtained. The lugs 19 near the mid-point of the unit are united as indicated at 23 and give additional strength at this point. 7-

The solid bottomof-the unit comprises a plate which extends a short distance into the cap member below the lower edge thereof and is locked thereto in any convenient manner. For example, the cap member may be provided with openings 24 which lie below the top ofthe solid bottom so that as the latter is formed by a casting operation, the metal will flow through these openings to Vform locking tongues 25. If desired, the bottom plate maybe provided with lugs 26 which are placed to correspond with the lugs 18 and to form continuations thereof.

The bottom plate is formed witha recess 27 in its lower edge, the recess having a shape similar to the cross-sectional shape of the carrier. At the entrance of the recess, the plates are formed with opposed lugs 28 so positioned that when a relative movement of the unit and carrier occurs during the shaking of the grate, one or the other of the lugs 28 will come into contact with the under surface of the web, preventing further angular movement of the unit and carrier relative to one another and locking the unit to the carrier. Preferably the shape of the recess is such that the unit rests on the iiat surface 29 at the top of the web on opposite sides of the flange 11, and does not contact with the flange. The lower edge of the cap member is also appropriately formed for this purpose.

With the construction described, it will be noted that a substantial proportion of the unit is hollow and formed oflight Weight stock so that the total weight of the unit is substantially less than that of a solid unit of the same size.` Also, the

cap member which is preferably of sheet steel substantially prevents fracture of the solid part of the unit, and if fracture occurs, the two parts of the cast bottom will be heldr together by the cap member so that the loss of the injured unit from the cross-bar is entirely prevented.

The cap member'can be made of sheet metal at low cost by stamping operations and the finished cap member is then placed in a mold and the bottom part of the unit formed by casting. The molten metal enters the cap member to effect proper union of the cap member and bottom in the manner described.

What I claim:

1. In a grate bar, a fuel supporting unit which comprises a solid base portion and a hollow fuelsupporting top portion, said base portion having 'a part at its top lying within said hollow fuelsupporting portion and said base and fuel-'supcomprises a hollow fuel supporting portion of pressed steel and a solid base portion of cast iron. Y y y 4. In a grate bar, a fuel supporting.y unit which comprises a hollow cap member formed to define I spaced vertical lugs on atleast one face, and a solid base having its ltop lying within the cap` member, said cap member and base having interengaging parts permanently locking the cap member and base together.

5. In a grate bar, a fuel supporting unit which comprises a hollow cap member formedto define v shaped to define spaced vertical lugs projecting from at least one face and terminating at their tops in fuel supporting projections extending upwardly, and a solid base member of cast iron to which lthe cap member is secured.

'7. A grate'bar which comprises a longitudinal member and fuel supporting cross bars mounted thereon and projecting beyond at least one edge thereof, each cross bar comprising a hollowfuel supporting top, and a solid base having a part lying within said top, said top and base having interengaging parts permanently locking them together and saidl base having an opening in which said longitudinal member is received.

S. A gratel bar which comprises a longitudinal memberpand fuel ,supportingcross bars mounted thereon and projecting beyond at least .one edge thereof, each cross bar comprising a hollow fuel supporting portion of pressed steel( and a solid base portion extending into said hollow portion and anchored thereto, said base portion resting incontact with said member and having a recess in which said member is received.

9. In a grate bar, a' fuel supporting unit comprising a hollow cap member formed with spaced rvertical lugs along at least one face, and a solid base member having its top lying within said cap member, said top and cap member having interengaging parts for permanently connecting said members, and said base member havinglugs on at least one face constituting continuations of those on the cap member.

JAMES S. THOMPSON. 

